Pick-up rollers with a flat section

ABSTRACT

A pick-up roller (100) comprises a circular body (116) to transition print media towards a print path, the circular body (116) includes a first flat surface (118), a first rim (114) connected to a first distal end (126) of the circular body (116), and a second rim (122) connected to a second distal end (128) of the circular body (116); and a cylindrical connector (124) coupled to the second rim (122), wherein a flat portion of the cylindrical connector (124) is coupled to the second rim (122).

BACKGROUND

A pick-up roller of a printing device may be a cylindrical member, for instance, a rubber coated wheel. The pick roller may contribute to retrieval of a print medium, such as a sheet of paper, by engaging it and rotating to feed the print medium into a print zone of the printing device.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates an example of a pick-up roller consistent with the disclosure.

FIG. 2 illustrates an example of a system including a printing device and a pick-up roller consistent with the disclosure.

FIGS. 3A-3B illustrate perspective views of an example pick-up roller consistent with the disclosure.

FIG. 4 illustrates an example of a pick-up roller including circular bodies consistent with the disclosure.

DETAILED DESCRIPTION

A pick-up roller may include a circular body to rotate and transition print medium from a print media basket into a print path. The circular body may be connected to a cylindrical connector. As the circular body rotates, the frictional force between the print medium and the pick-up roller may cause the print medium to transition into the print path of the printing device.

The ability of the pick-up to transition print media into the printing device may be hindered by particles that adhere to the pick-up roller during the transition of print media. The hindrance may be dust or other atmospheric particles that have accumulated over time. The accumulation of particles on the pick-up roller may decrease the frictional force between the pick-up roller and the print media. The particles may be, for instance, talc powder that is inherent within most print media. The particles may build up on the pick-up roller and decrease the frictional force between the print media and the pick-up roller, making it difficult for the pick-up roller to transition the print media towards the print path.

A pick-up roller, as described herein, may include a circular body to transition print media towards a print path. The circular body may include a first rim and a second rim positioned at the distal end of the circular body, a cylindrical connector coupled to the circular body, and a flat surface that increases the frictional force between the print media and the pick-up roller. Accordingly, this disclosure describes a pick-up roller that increasing the area of the pick-up roller that comes in contact with the print medium by including a flat surface in the circular body to increase the frictional force.

The figures herein follow a numbering convention in which the first digit corresponds to the drawing figure number and the remaining digits identify an element or component in the drawing. For instance, element 118 in FIG. 1 refers to element “18”, which may be analogous to element 318, referring to element “18” in FIG. 3.

FIG. 1 illustrates an example of a pick-up roller 100 consistent with the disclosure. The pick-up roller 100 may be implemented in a variety of printing devices. As used herein, “printing device” refers to a hardware device with functionalities to physically produce representation(s) of text, images, models, etc. on a print medium and/or produce a three-dimensional object. Examples of printing devices include ink/toner printers and/or three-dimensional printers, among other types of printing devices. In some examples, the pick-up roller 100 may include a circular body 116. The circular body 116 may assist in the transitioning of a print medium from a print media basket towards a print path. That is, the circular body 116 may contact a print medium and transition the print medium towards the exit of the print media basket into a print path of a printing device. It should be understood that when an element is referred to as being “on,” “in contact,” “connected to”, or “coupled to” another element, it may be directly on, in contact, connected, or coupled with the other element or intervening elements may be present. In contrast, when an object is “directly coupled to” or “directly coupled with” another element it is understood that are no intervening elements (adhesives, screws, other elements, etc.). In some examples, the pick-up roller may be positioned above a print media basket. In some examples, print media may be positioned between the print media basket and the print media. As used herein, “print media” refers to a plurality of papers, photopolymers, plastics, composites, metals, woods, or other material on which markings may be formed. As used herein, “print medium” refers to an individual paper, photopolymer, plastic, composite, metal, wood, or other material on which markings may be formed. As used herein, a “print media basket” refers to a compartment in a printing device that houses print media.

In some examples, the diameter of the circular body 116 may range from about 10.0 millimeters (mm) to about 20.0 mm, including all subranges and individual value in between. For instance, in some examples, the circular body 116 may range from about 10.0 mm to about 20.0 mm, 11.5 mm to about 20.0 mm, 13.0 mm to about 20.0 mm, 14.5 mm to about 20.0 mm, 16.0 mm to about 20.0 mm, 17.5 mm to about 20.0 mm, 18.5 mm to about 20.0 mm, 10.5 mm to about 19.5 mm, 10.5 mm to about 18.0 mm, 10.5 mm to about 17.0 mm, 10.5 mm to about 16.5 mm. As used herein, “about” refers to characteristics are close enough to achieve the same function but does not have to be absolute.

In some examples, the circular body 116 may include a flat surface 118. The flat surface 118 may increase the coefficient of friction of the pick-up roller 100, as compared to a pick-up roller without a flat surface 118. As used herein, “coefficient of friction” refers to the ratio between the force necessary to move one surface horizontally over another and the pressure between the two surfaces. In an example including a flat surface 118, as a pick-up roller transitions print media towards the print path, particles such as talc powder from the print media may accumulate on the pick-up roller. As the particles accumulate, the coefficient of friction of the pick-up roller may decrease, thereby reducing the amount of print media the pick-up roller transitions into the print path.

Including a flat surface 118 in the structure of the circular body 116 may increase the coefficient of friction of the pick-up roller, as compared to a pick-up roller without a flat surface 118. That is, a circular body 116 including a flat surface 118 may transition print media towards the exit of the print media basket, without being hindered by the particles accumulating on the pick-up roller 100. As used herein, “flat” refers to a substantially smooth and/or even object. For example, “flat surface” refers to a substantially smooth and or even surface of an object. In addition, “flat portion” refers to a substantially smooth and or even portion of an object. As used herein, “substantially” intends that the characteristic does not have to be absolute but is close enough so as to achieve the characteristic. For example, “substantially aligned” is not limited to absolutely aligned. For example, “substantially smooth” is not limited to absolutely smooth.

In some examples, the area of the flat surface 118 is based on the dimension of the circular body 116. That is, the area of the flat surface 118 may be derived from the width (W) of the circular body 116, the diameter (D) of the circular body 116, and the distance between the flat surface 118 and the center of the of the circular body 116 (e.g., length (L)). For example, the area (S) of the flat surface 118 may be determined by to following:

$\begin{matrix} {S = {2W\sqrt{\frac{D^{2}}{4} - L^{2}}}} & \left( {{Equation}\mspace{14mu} 1} \right) \end{matrix}$

As described in further detail below, increasing the area of the pick-up roller 100 that comes in contact with the print media may increase the coefficient of friction.

In some examples, the pick-up roller 100 may include a first rim 114 coupled to a first distal end 126 of the circular body 116. As used herein, “rim” refers to the outer edge of an object. The first rim 114 may extend past the circular body 116 to keep a body cover in place. For example, the first rim 114 may extend past the circular body 116 preventing a body cover, positioned around the circular body 116, from sliding off through the first distal end 126. That is, the circumference of the first rim 114 may be larger than the circumference of circular body 116. As used herein, “distal end” refers to ends that are within five percent of the outer most regions of an object. However, this disclosure is not so limited. In some examples, the pick-up roller 100 may not include a first rim. That is, the body cover may remain positioned around the circular body 116 without a first rim 116.

In some examples, the pick-up roller 100 may include a second rim 122 coupled to a second distal end 128 of the circular body 116. The second rim 122 may extend past the circular body 116. That is, the circumference of the second rim 122 may be larger than the circumference of circular body 116. The second distal end 128 may be parallel to the first distal end 126. Similarly, the second rim 122 may be parallel to the first rim 114. In some examples, the second rim 122 may be positioned to keep a body cover from moving off of the circular body 116. For example, a body cover may be positioned around the circular body 116, and the second rim 122 may extend past the circular body 116 preventing a body cover from sliding off the circular body 116 through the second distal end 128. However, this disclosure is not so limited. In some examples, the pick-up roller 100 may not include a second rim. That is, the body cover may remain positioned around the circular body 116 without a second rim 116.

In some examples, the circumference of the first rim 114 and the circumference of the second rim 122 may be the same. However, this disclosure is not so limited. In some examples, the circumference of the first rim 114 and the circumference of the second rim 122 may be different. For example, the circumference of the first rim 114 may be larger or smaller than the circumference of the second rim 122. The circumference of the first rim 114 and the second 122 may be larger than the circumference of the circular body 116. In some examples, the pick-up roller 100 may include a first rim 114 and not a second rim 122. In contrast, the pick-up roller 100 may include a second rim 122 and not a first rim 114.

In some examples, the pick-up roller 100 may include a cylindrical connector 124 coupled to the second rim 122. For instance, the flat portion of the cylindrical connector 124 may be coupled to the second rim 122, as shown in FIG. 1. However, the disclosure is not so limited. In some examples, the cylindrical connector 124 may be coupled to the second distal end 128 of the circular body 116. That is, the flat portion of the cylindrical connector 124 may be in contact with the second distal end 128 of the circular body 116. In some examples, the cylindrical connector 124 may connect a first circular body to a second circular body. That is, the cylindrical connector 124 may include two flat portions and each flat portion may be connected to a circular body 116, as described in detail below.

FIG. 2 illustrates an example of a system 201 including a printing device 203 and a pick-up roller 200 consistent with the disclosure. In some examples, the system 201 may include a pick-up roller 200. The pick-up roller 200 may be comprised of a circular body 216 to transition print media, when present, towards the print path 208. In some examples, the circular body 216 may include a flat surface 218 to assist in transitioning the print media towards the print path 208. That is, the circular body 216 including a flat surface 218 may rotate in a clockwise direction to transition print media in a direction denoted by the arrow 255. In some examples, the print media may be housed in a print media basket 204. The printing device 203 may include a print media basket 204 to house print media.

In some examples, the pick-up roller 200 may include a body cover 230. In some examples, the body cover 230 may be positioned around the circular body 216. In some examples, when the body cover 230 is positioned around the circular body 216 the body cover 230 may conform to the shape and/or structure of the circular body 216. That is, the flat surface 218 may form through the body cover 230. In some examples, the flat surface 218 may come in contact with print medium to transition the print medium towards the print path 208. That is, the pick-up roller 200 including the flat surface 218 may transition print medium through an upwards slope 206 of the printing device 203 into the print path 208. In some examples, the pick-up roller 200 including the flat surface 218 may transition the print media through the slope with a height of from about 5 mm to about 15 mm, including all individual values and subranges in between.

For instance, as the pick-up roller 200 rotates, the frictional force between the body cover 230 and the print medium may cause the print medium to transition up the slope 206 and into the print path 208. That is, a higher frictional force may allow more print media to transition towards the print path 208 than a lower frictional force. For instance, when retrieving print media stacked in the print media basket 204, the greater the frictional force applied to each sheet of print medium, to press it against the pick-up roller 200, the larger the possibility that a plurality of print media may be retrieved by the print path 208 of the printing device 203 simultaneously. In some examples, the frictional force of the body cover 230 may be increased by the inclusion of a flat surface 218. As used herein, “frictional force” refers the amount of force used to pick up print media and/or transition print media to the print path. In some examples, the frictional force may be represented by Equation 2, where F is the frictional force, μ is the coefficient of friction, and N is the normal force. For instance:

F=μN  (Equation 2)

Particles may accumulate on the body cover 230 of the pick-up roller 200 as print media comes in contact with the body cover 230. The particles accumulating on the body cover 230 may reduce the frictional force between the pick-up roller 200 and the print media. Reducing the frictional force between the pick-up roller 200 and the print media may reduce the amount of print media the pick-up roller 200 is able to transition towards the print path 208. In some examples, increasing the area of the body cover 230 that comes in contact with the print medium may increase the frictional force. For instance, increasing the area of the body cover 230 that comes in contact with the print media may increase the coefficient of friction (μ), which in turn increases the frictional force, as illustrated in Equation 2.

In some examples, the flat surface 218 of the pick-up roller 200 may increase the area of the body cover 230 that comes in contact with the print media as the pick-up roller 200 transitions the print media towards the print path 208. That is, including a flat surface 218 may increase the amount of the body cover 230 that comes in contact with the print media at an individual time. As discussed above, increasing the amount of area of the body cover 230 that comes in contact with the print media increases the coefficient of friction, which in turn may increase the frictional force.

In some examples, as the pick-up roller 200 rotates in a clockwise direction, the entire flat surface 218 may come in contact with print media, positioned on the print media basket 204, at an individual time. Increasing the area of the body cover 230 that contacts the print media increases the coefficient of friction, thereby increasing the frictional force. As such, the entire flat surface 218 contacting the print media at an individual time may increase the amount of print media that is picked up by the pick-up roller 200 and transitioned up the slope 206 into the print path 208. That is, increasing the amount of frictional force applied to each sheet of print medium may increase the amount of print media the pick-up roller 200 transitions from the print media basket 204 into the print path 208.

FIGS. 3A-3B illustrate perspective views of an example pick-up roller 300 consistent with the disclosure. In some examples, the pick-up roller 300 may include a circular body 316. The circular body 316 may rotate to transition print media towards a print path. The pick-up roller 300 may include a flat surface 318 to increase the area of the pick-up roller 300 that contacts a sheet of print media at an individual time. However, this disclosure is not so limited. In some examples, the pick-up roller 300 may include a plurality of flat surfaces to increase the area of the pick-up roller 300 that comes in contact with print media at an individual time. For example, the pick-up roller 300 may include two flat surfaces that are parallel to each other.

As described above, increasing the area of the pick-up roller 300 that comes in contact with print media may increase the coefficient of friction. Further, increasing the coefficient of friction may cause the frictional force to increase, according to Equation 2. In addition, increasing the frictional force may result in a sufficient frictional force to transition print media into a print path, as particles accumulate on the pick-up roller 300. As such, a pick-up roller 300 including a flat surface 318 may ensure there is sufficient frictional force to transition print media into a print path.

In some examples, the pick-up roller 300 may include a body cover 330 positioned around a circular body 316. In some examples, the body cover 330 may be removably coupled to the circular body 316. However, this disclosure is not so limited. In some examples, the body cover 330 may be permanently coupled to the circular body 316. As used herein, “removably coupled” refers to an object connected and/or combined to another object that can disconnected. As used herein, “permanently coupled” refers to an object connected and/or combined to another object that cannot disconnected.

In some examples, the body cover 330 may be positioned around the circular body 316 with a press fit that prevents the body cover from sliding off the circular body 316. That is, the body cover 330 may remain on the circular body 316 without a first rim (e.g., first rim 114 of FIG. 1) or a second rim (e.g., second rim 122 of FIG. 1). As used herein, “press fit” refers to a fit between the body cover and the circular body, in which the circular body is forced under pressure into the slightly smaller hole of the body cover. In some examples, the body cover 330 may conform to the shape and/or structure of the circular body 316. That is, the flat surface 318 may appear through the body cover 330, thereby increasing the area of the body cover 30 that comes in contact with print media.

In some examples, the body cover 330 may have a coefficient of friction greater than 1.5 Newtons (Nw). That is, the coefficient of friction of the body cover 330 may range from of about 1.5 Nw to about 2.3 Nw, including all individual values and subranges in between. In some examples, including a flat surface 318 may increase the coefficient of friction of the body cover 330 by a range of from about 0.5 Nw to about 2 Nw. In some examples, the body cover 330 may be made of elastomeric material. As used herein, “elastomeric material” refers to a material that exhibits elastic or rubber-like properties. However, this disclosure is not so limited. That is, the body cover 330 may be made of a material with a coefficient of friction greater than 1.5 Nw.

In some examples, the pick-up roller 300 may include a cylindrical connector 324-1. The flat portion of the cylindrical connector 324-1 may be coupled to the second distal end 328 of the circular body 316. In some examples, the circular body 316 may be coupled to a plurality of cylindrical connectors 324. Cylindrical connectors 324 collectively refers to cylindrical connector 324-1 and cylindrical connector 324-2. For example, the circular body 316 may be connected to both cylindrical connector 324-1 and cylindrical connector 324-2. The flat portion of the cylindrical connector 324-2 may be coupled to the first distal end 326 of the circular body 316. In some examples, the cylindrical connectors 324 may connect the pick-up roller 300 to a printing device (e.g., printing device 203 of FIG. 2). The cylindrical connectors 324 may assist the circular body 316 in rotating, as the circular body 316 transition print media into the print path.

FIG. 4 illustrates an example of a pick-up roller 400 including circular bodies 416 consistent with the disclosure. In some examples, the pick-up roller 400 may include a cylindrical connector 424. The cylindrical connector 424 may connect to a plurality of circular bodies 416. Circular bodies 416 collectively refers to first circular body 416-1 and second circular body 416-2. For example, the flat portions of the cylindrical connector 424 may connect to a second distal end of a first circular body 416-1 and a second distal end 428-2 of a second circular body 416-2. First circular body 416-1 and second circular body 416-2 may be collectively referred to herein as circular bodies 416. In some examples, the cylindrical connector 424 may transition with the circular bodies 416 to transition print media into a print path.

In some examples, the cylindrical connector 424 may connect to a plurality of circular bodies 416 through a second rim coupled to each of the circular bodies 416. That is, the flat portions of the cylindrical connector 424 may connect to a second rim of the first circular body 416-1 and a second rim of the second circular body 416-2. While FIG. 4 illustrates first circular body 416-1 and second circular body 416-2, additional or different circular bodies may be present.

In some examples, the circular bodies 416 may be comprised of plastic. For example, the circular bodies 416 may be made of Acrylonitrile Butadiene Styrene (ABS), Polycarbonate (PC), High Impact Polystyrene (HIPS), or a combination thereof. However, the disclosure is not so limited. That is, the circular bodies 416 may be comprised of other suitable plastics. In some examples, the circular bodies 416 may be comprised of metal. For example, the circular bodies 416 may be made of steel, stainless steel, brass, aluminum, or a combination thereof. In addition, the circular bodies 416 may be comprised of other suitable metals.

In some examples, the pick-up roller 400 may include a plurality of flat surfaces (e.g., first flat surface 418, second flat surface 420, and third flat surface 432). First flat surface 418, second flat surface 420, and third flat surface 432 may collectively refer to first flat surfaces 418-1 and 418-2, second flat surfaces 420-1 and 420-2, and third flat surfaces 432-1 and 432-2, respectively. In some examples, first circular body 416-1 may include a first flat surface 418-1, a second flat surface 420-1, and a third flat surface 432-1. Similarly, second circular body 416-2 may include a first flat surface 418-2, a second flat surface 420-2, and a third flat surface 432-2.

In some examples, the first flat surface 418-1 of the first circular body 416-1 and first flat surface 418-2 of the second circular body 416-2 may be substantially aligned. In addition, the first flat surface 418-1 of the first circular body 416-1 and the first flat surface 418-2 of the second circular body 416-2 may remain in alignment as the pick-up roller 400 rotates. Similarly, the second flat surface 420-1 of the first circular body 416-1 and second flat surface 420-2 of the second circular body 416-2 may be substantially aligned. In some examples, the second flat surface 420-1 of the first circular body 416-1 and second flat surface 420-2 of the second circular body 416-2 may remain in alignment as the pick-up roller 400 rotates. Likewise, the third flat surface 432-1 of the first circular body 416-1 and third flat surface 432-2 of the second circular body 416-2 may be substantially aligned. In some instances, the third flat surface 432-1 of the first circular body 416-1 and third flat surface 432-2 of the second circular body 416-2 may remain in alignment as the pick-up roller 400 rotates. As used herein, “aligned” refers to objects arranged in a substantially straight line, parallel to each other.

In some examples, the pick-up roller 400 may include body covers 430. Body covers 430 may collectively refer to first body covers 430-1 and second body covers 430-2. In some examples, first body cover 430-1 may be coupled to first circular body 416-1. Similarly, second body cover 430-2 may be coupled to second circular body 416-2. The body covers 430 may conform to the shape and/or structure of the circular bodies 416. For example, if the circular bodies 416 include a flat surface (e.g., first flat surface 418, second flat surface 420, and/or third flat surface 432) in the structure, the body covers 430 may include a flat surface as well.

In some examples, as the pick-up roller 400 rotates, the entire flat surface of the flat surfaces formed in the body covers 430 may come in contact with print medium. Increasing the area of the body covers 430 that comes in contact with the print medium, at an individual time, may increase the coefficient of friction, which in turn increases the frictional force. In addition, increasing the area of the body covers 430 that comes in contact with the print media, at an individual time, may increase the amount of print media that is picked up by the pick-up roller 400 and transitioned into the print path.

Elements shown in the various figures herein may be capable of being added, exchanged, and/or eliminated so as to provide a number of additional examples of the disclosure. In addition, the proportion and the relative scale of the elements provided in the figures are intended to illustrate the examples of the disclosure and should not be taken in a limiting sense. It should be understood that the descriptions of various examples may not be drawn to scale and thus, the descriptions may have a different size and/or configuration other than as shown therein.

While some elements are designated as a “top,” “above,” or a “bottom,” it should be understood that such elements may correspond to other relative terms or possible orientations in some applications in order to practice the examples of this disclosure. 

1.
 1. A pick-up roller comprising: a circular body to transition print media towards a print path, the circular body including: a first flat surface; a first rim connected to a first distal end of the circular body; and a second rim connected to a second distal end of the circular body; and a cylindrical connector coupled to the second rim, wherein a flat portion of the cylindrical connector is coupled to the second rim.
 2. The pick-up roller of claim 1, wherein the circular body includes a second flat surface.
 3. The pick-up roller of claim 2, wherein the second flat surface is parallel to the first flat surface.
 4. The pick-up roller of claim 1, wherein a diameter of the circular body ranges of from about 10.0 millimeters (mm) to about 20.0 mm.
 5. A system comprising: a printing device including a print media basket to house print media; and a pick-up roller to transition the print media, when present, from the print media basket towards a print path, wherein the pick-up roller is positioned above the print media, when present, the pick-up roller including: a circular body comprising a flat surface; and a body cover to positioned around the circular body.
 6. The system of claim 5, wherein the body cover is comprised of an elastomeric material.
 7. The system of claim 6, wherein the body cover is removably coupled to the circular body.
 8. The system of claim 6, wherein the body cover is to conform to the structure of the circular body.
 9. The system of claim 5, wherein the pick-up roller is to transition the print media through an upwards slope of the printing device to transition the print media towards the print path.
 10. The system of claim 9, wherein the pick-up roller is to transition the print media through the slope with a height of 15 millimeters (mm).
 11. A pick-up roller comprising: a first circular body to exert a force on print media to transition the print media up a slope, the first circular body including: a flat surface; and a rim connected to a distal end of the first circular body; a cylindrical connector connected to the first circular body, wherein the cylindrical connector is coupled to the distal end of the first circular body; and a body cover coupled to the first circular body.
 12. The pick-up roller of claim 11, wherein an area of the flat surface ranges of from about 40 square millimeters (mm²) to about 200 mm².
 13. The pick-up roller of claim 11, wherein the pick-up roller has a second circular body attached to the cylindrical connector.
 14. The pick-up roller of claim 11, wherein the first circular body is made of plastic, wherein the plastic is further comprised of Acrylonitrile Butadiene Styrene (ABS), Polycarbonate (PC), High Impact Polystyrene (HIPS), or a combination thereof.
 15. The pick-up roller of claim 11, wherein the first circular body is made of metal, wherein the metal is further comprised of steel, stainless steel, brass, aluminum, or a combination thereof. 